The composite glucose, energy and myoinositol metabolism of the neural components of peripheral nerve from normal and alloxan diabetic rabbits will be compared by studies of incubated preparations of an isolated rabbit tibial nerve fascicle and of its endoneurial contents. The dependence of the maintenance of a high tissue to extracellular fluid free myoinositol gradient upon the maintenance of a steady state of energy metabolism in tissue from normal rabbits will be examined. The enzymatic capacity for free myoinositol synthesis in the neural components of peripheral nerve will be assessd and compared with that in tissue from alloxan diabetic rabbits. The role of fructose as a substrate for energy production in this tissue will be examined to explain the inability of the high tissue fructose concentrations in fascicles and "endoneurial" tissue from normal rabbits to maintain a steady state of energy metabolism in the absence of exogenous substrate and to evaluate the possible effects of the extremely high fructose concentrations found in tissue from diabetic rabbits. The composite glucose, polyol pathway, energy and myoinositol metabolism of aortic intima-media from normal and alloxan diabetic rabbits will be compared by studies of incubated "intact" aortic intima-media preparations. Studies will be undertaken to determine the feasibility of employing a quantitative histochemical and morphometric approach to the assessment of endothelial metabolism in this tissue. The capacity for the incorporation of U-14C-glucose and 35S-SO4 into the heparan sulfate fraction of glycosaminoglycans will be examined in the vascular stroma of rat epididymal fat pads, rabbit aortic intima-media, and rat kidney cortex slices and isolated glomeruli, and the effects of insulin and experimental diabetes examined.